Educators have long been fascinated by the possibility of using groups to transform and revitalize classroom learning. For us, the promise of cooperative learning derives mainly from its equity orientation, namely the potential for encouraging constructive reasons for learning that are within the reach of all students.

There is little doubt that working toward a larger, common purpose can motivate students individually to their best efforts. A commonplace example is team sports, like volleyball, where the team's success depends on the joint and individual contributions of all its members. If the team wins, all savor victory – another source of equality, that is, a shared payoff – and if the team loses, then all suffer defeat collectively. Maximum effort is thereby assured because being rewarded individually depends on each team member trying his or her hardest (Deutsch, 1949). Many variants of cooperative learning have evolved over the years, but two types predominate.

Group-contribution mode

First, consider the group-contribution mode (Slavin, 1983, 1984). Here team members work or study together to produce a single product – perhaps a mural, a worksheet, or a report (e.g., Sharan & Sharan, 1989–1990). If the product measures up to the prevailing standards, then all members are rewarded, no matter how many other teams may also be working on the same task. Under this arrangement, the role of an individual team member may not be clear, and not everyone's contributions will necessarily be equally important.